Means for making articles having a polygonal cross section



R. L.' WILCOX Aug. 28, 1934.

MEANS FOR MAKING ARTICLES HAVING A POLYGONAL CROSS SECTION n Original Filed May l5, 1933 WL r 7/4 y;

1N VEN TOR. R/cH/:RD 5727? W/cax A TTORNEY.

Patented Aug. 28, 1934 UNITED STATES PATENT oFEIcE MEANS FOR MAKING ARTICLES HAVING A PoLYGoNAI. cnoss sEcTIoN ration of Connecticut Original application May 15, 1933, Serial No.

Divided and this application September 2, 1933, Serial No. 687,984

9 Claims.

This invention relates to means for making articles in a cold state having a polygonal cross section, and as disclosed herein, is applied to the formation of articles such as a nut blank or the like.

This application is a division of an application led May 15, 1933, by this applicant, and designated by the Serial Number 671,166.

In the co-pending application there is shown and described a means and method for making articles having a polygonal cross section by a cold process from a substantially cylindrical blank that is initially longer than the height of the iin-l ished article and of less cross sectional area, by 5 means that provide for the minimum wastage of metal and a flow of metal during the several operations that will require the minimum pressure; and further, to provide a chamfer on either or both sides of the blank as may be desired, this latter being produced by the flow of the metal as distinguished from a pressure operation and the article, when completed, will be of superior toughness, both in the body of the nut and the walls of the openings therethrough.

This present invention particularly relates to the means and the apparatus by which pressures are applied to the blank.

As illustrated and described herein, the invention is applied in the manufacture of an article having an hexagonal cross section, but is not limited, however, to such shape.

In the accompanying drawing, wherein like numerals of reference indicate like parts in the several figures;

Figure l is a sectional view of the mechanism utilized in this invention;

Figure 2 is a transverse sectional view of a portion thereof, the parts in section being taken generally on line 2 2 of Figure 1, the relative position of the parts, however, in this view being different than in Figure 1;

Figure 3 is a fragmentary plan View of the forming die;

Figure 4 is a sectional view on an enlarged scale of the blank as produced by the rs't pressure operation;

Figures 5 and 5A are views of the blank after a succeeding pressure operation and in its completed exterior shape; and

Figures 6 and 6A are views of lthe completed article.

By the means herein disclosed, a blank, whether cut from a wire rod, or otherwise produced, is by pressure countersunk at the opposite ends and thereafter subjected to pressure upon its ends.

This pressure reduces its height and increases its diameter, so that it is slightly larger than the distance across the corners of the completed article.' Thereafter, by lateral pressure, the blank is shaped into its substantially completed form, the depressions therein being substantially the same size as the opening or hole through the blank, and formed through the last pressure with a comparatively thin web between the bottoms thereof. Thereafter, this web is removed and the nut is in its completed form ready for the threading operation.

The improved mechanism herein disclosed may be associated with a power press, header or the like, although not necessarily limited thereto.

` The numeral 10 designates the die bed that is secured to the body l1 of the machine, and upon which is xed a die block 12 in any preferred manner. Within this latter is a pressure die 13 and forming die 14. The pressure die 13 has a 75 recess 15 in its face, which is substantially the same diameter as the blank 16, the bottom corners thereof being preferably angular to form a chamfer on one face of the blank. Within this die 13 is a recess 46 enclosing a punch 17, having a head 80 18, which rests against the anvil block 19, and a coil spring 20 between the head 18 and an end wall of the recess. Between the head 18 and the knockout rod 21 is an ejector pin 22. When the head 18 is against the anvil block 19, the outer end of the punch 17 forms a bottom for the recess in the die 13. The end of the punch 17 is pointed and forms a depression in one face of the blank.

A plunger or gate 23 is actuated in any well know manner toward and away from the die block 12. Associated and movable with the plunger or gate 23 is a backing plate 24, against which contacts the punch 25 and the punch carrier 26. The face of the punch 25 is provided with a recess 27, having angular corners at the bottom thereof to form a chamfer upon one face of the blank 16. Within the punch 25 is a punch 2'8 that is substantially the same diameter as the punch 17 and having a tip corresponding therewith.

The blank 16 presented to the pressure die 13 is provided with a central depression, and the punches 17 and 28 have conical ends with an angle of inclination that is flatter than that of the depression formed in the blank as presented to the pressure die 13. These depressions are shown more particularly in enlarged view Figure 4, being severally designated 29 and 30. When the inner end of the punch 28 contacts with the plate 110 'formed by the prior operations.

24 its outer conical end is in upsetting pressure position.

The knockout rod 21 insures the ejection of the blank from the recess in the pressure die 13 and likewise from the recess in the punch 25 through the punch 28 and coil spring 31.

The blank is presented in line with the pressure die 13 and punch 28 and centered relatively thereto by the tips of the punches 17 and 28, which hold the blank against relative movement while the transfer mechanism (not shown) is being disengaged therefrom. Between these punches the height of the blank is reduced, the metal flowing outwardly and filling the recesses in the die 13 and punch 25 and the tips of the punches 17 and 23 forming a depression in the opposite face of the blank substantially as shown in Figure 4. Each of these tips has a at end and angular walls, which increase the circular area of the depressions in the blank without losing the tapered center at the bottom of the depressions as formed in a prior pressure operation.

The angular corners formed on the blank in this last operation insure the formation of cham- Aiered corners on opposite faces of the finished article. Obviously, the blank may be formed with a chamfer on one end face only if desired.

The forming die 14 comprises a body member 36 through which is an opening 44 and through the walls of the smaller diameter thereof are six radial slots 45 at an angle to the axisof the opening 44, as this die is designed to produce an article hexagonal in cross section. A greater or less number of faces on the article correspondingly increase or reduce the number of radial slots.

Movable in each slot is a pressure die 35 having a straight inner face 47 and angular adjacent faces 48, which contact with each other when the pressure dies are in their innermost position. Each pressure die has an outer cam face 49 which rides against the angular walls of the slots, an inner cam face 50 and a stop shoulder 51. Movably mounted within the opening 44 and bushing 52 is a sleeve 37 having a coned head 39, the angular inclination of which is substantially the same as that of the cam faces 50 which engage therewith. Surrounding the sleeve 37 between the collar thereon and the bushing 52 is a coil spring 38. Within the sleeve 37 is a punch 34 having a head 53 thereon which is movable in a recess in the sleeve. Between the head and the end wall of the recess is a coil spring 54 which requires less pres- 4sure to compress than the spring 38.

Between the head 53 and the knockout rod 42 is ian ejector rod 55.

The tip 56 of the punch 34 corresponds in size with the opening or hole in the finished article and is longer than the depth of the depression Secured to-the body member, or other similar means, is the stop plate-41, having an opening therethrough, which is engaged by the stop shoulders 51 on the pressure dies 35, to limit their 'movement in one direction.

Within the punch carrier 26 is a punch 32 actuated in one direction by a coil spring 33 and of substantially the same diameter as the punch 34 and a tip of substantially the same shape. When the punch 32 contacts at its inner end with the backing plate 24, its outer end is in its pressure position.

The blank 16 is transferred into line with the punches 32 and 34 and the tops of each project into the depressions in opposite faces of the blank and center and hold it while the transfer mechanism is disengaged therefrom. The blank is supported between these two punches while the plunger or gate 23 is moving toward the bed 10 and carried intoposition between the pressure dies 35, the punch 34 receding during this operat on.

The relative position of the parts of the forming die 14, as the blank is about to be presented thereto, and whileheld by the transfer mechanism, is shown in Figure 2.

As the plunger or gate 23 continues its movement toward the bed 10 the end of the punch carrier 26 applies endwise pressure to the pressure dies 35 which move inwardly toward each other within the body member 36, and the sleeve 37 moves endwise away from the blank.

During the action of the punch carrier 26 the punch 32 recedes against the tension of the spring 33 and the face of each pressure die 35 is forced against the perimeter of the blank, changing its form from a cylindrical blank to one having a polygonal cross section and increasing its height. The sleeve 37 during this operation travels away from the blank, now held between the dies, faster than the metal flows, thus leaving an open space between it and the blank. Moving the sleeve 37 away from the blank permits unrestrained metal flow on the underside thereof substantially parallel with the axis of the blank.

As the spring 33 is relatively light there is practically no resistance to the fiow of the metal upwardly, as' the punch carrier 26 advances.

When the plunger or gate 23 travels away from the bed 10 a spring 38 pushes the sleeve 37 outwardly and engagement of the coned head 39 with the pressure dies 35 gives them' an outward movement away from the blank until the stop shoulders 51 engage the stop plate 4l. During this action the punch 34 is projected outwardly by the'y knockout rod 42, with the result that the blank is in the position substantially as shown in Figure 2 and ready for engagement lby the transfer mechanism. After the blank is engaged by the transfer mechanism the punches 34 and 32 are disengaged therefrom and the blank is ready for presentation at a succeeding station for further operations.

The blank after the forming die operation is in the form substantially as shown in Figure 5,

, wherein 43 indicates the thin web between the bottom of the depressions.

The tips of the punches are of less diameter and greater depth than the depressions in the blank as presented thereto. Therefore, the metal under the pressure of the pressure dies 35 flows around these tips and the former counter-sunk depressions now have a substantially uniform diameter, and the same as the opening or the hole in the nished article, of which these are now a part. Thus, the walls of said hole to be subsequently threaded are toughened and more homogeneous.

By the means herein shown a homogeneous and toughened nut is produced from a wire rod or length by means entirely automatic and with minimum wastage of material. Such nut is of superior quality and adapted for use in places where resistance to pressure and strain is especially desirable.

The above disclosure is given merely as an ernbodiment of the present invention, which is not to be considered as limiting the invention, the

scope thereof being determined by an under standing o1' thev present disclosure as one embodiment thereof and as particularly pointed out in the claims.`

What I claim as new is:

1. In mechanism of the character described for producing nuts; a forming die having a plurality of pressure dies; companion punches movable. toward and away from each other and into the forming die, each punch having a tip thereon of substantially the same diameter as the hole or opening in the nished nut and their combined height being less than that of the nished nut, said punches supporting the blank therebetween before the same is presented to the forming die and means for moving the pressure dies in one direction, said means moving away from one of the punches through the action thereof.

2. In mechanism of the character described for producing nuts; a forming die having a plurality of pressure dies movable toward and awa'y from each other; a punch within the forming die means for moving the pressure dies in one direction; a punch movable toward and away from the last mentioned punch, each punch having a tip oi substantially the same diameter as the hole or opening through the nished nut, that supports the blank to present it between the opposing faces of the pressure dies and carry the same away therefrom and thereby increase the space between said means and the blank, said means, through the action of the pressure dies moving away from the blank while the latter is under the pressure of the pressure dies.

3. In mechanism of the character described for producing nuts; a forming die having a plurality of pressure dies movable toward and away from each other; means for moving the pressure dies in one direction; a punch within the forming die; a punch movable toward and away from the last mentioned punch, each punch having a tip of substantially thesame diameter as the hole or opening through the finished nut, that supports the blank to` present it between the opposing faces of the pressure dies, said punches being movable toward each other while the blank is under the pressure of the pressure dies, where-l by the thickness of the web in the blank between the opposing faces of the tips is predetermined, and the said means moves away from the blank and thereby increases the space between the said means and the blank.

4. In mechanism of the character described for producing nuts; a forming die having a plurality of pressure dies moving toward and away from each other; a member associated with the pressure dies for moving the same in one direction; a punch mounted within said member and having motion independent thereof; a second punch movable toward and away from the forming die, each of said punches having a part thereon which engages and holds the nut blank therebetween and while in such relative vposition-the blank is presented to and removed from the pressure dies; and a member having movement relative to said punches for actuating the pressure dies in the opposite direction.

5. In mechanism of the character described for producing nuts; a forming die having a. plurality of pressure dies moving toward and away from each other; a member associated with the pressure dies for moving the same in one direction; a punch mounted within said member and having motion independent thereof; a second punch movable toward and away from the forming die, each of said punches having a part thereon which engages and holds the nut blank theresure dies for moving the same in one direction;l

a punch mounted within said member and having motion independent thereof; a second punch movable ytoward and away from the forming die, each of said punches having a part thereon which engages and holds the nut blank therebetween and while in such relative position the blank is presented to and removed from the pressure dies; yielding means for actuating said member during the removal of the blank from the pressure dies located between a part connected with the first mentioned punch and said member; and a member having movement relative to said punches for actuating the pressure dies in the opposite direction. V

7. In mechanism of the character described for producing nuts; a forming die having a plurality of pressure dies moving toward and away from each other; stop means for limiting the movement of the pressure dies in one direction; a member associated with the pressure dies for moving the same in one direction; a punch mounted within said member and having motion independent thereof; a second punch movable toward and away from the forming die, each of said punches having a part thereon which engages and holds the nut blank therebetween and while in such relative position the blank is presented to and removed from the pressure dies; yielding means for actuating said member during the removal of the blank from the pressure dies and until its motion is prevented by the stop means; and a member having movement relative to said punches for actuating the pressure dies in opposite direction.

8. In mechanism of the character described for producing nuts, a forming die having a plurality of pressure dies movable toward and away from each other; companion punches having movement toward and away from each other and into and axially of the forming die; a member for moving the pressure dies in one direction, that is actuated in one direction away from one of said punches; and an independent device for Amoving the member in the opposite direction.

9. In mechanism of the character described for producing nuts; a forming die having a plurality oi pressure dies moving toward and away from each other and when in their inmost position forming a cavity or opening having a cross sectional shape that is substantially the same as that of the nut; companion punches for applying pressure to a nut blank and while the nut blank is in said cavity one of said punches initiating the inward movement of said pressure dies; and means independent of said punches for moving said pressure dies to their out positions.

RICHARD LESTER WILCOX. 

